Metal coating for arc-light electrodes.



B, PERRIS,

METAL COATING FOR ARC LIGHT ELECTRODES.

APPLVICATION HLED-OCT. 25. 1912.

1,148,189. Patented July 27, 1915.

' COATINQ OF METAL POWDER WITNESSES INVENTOR MW BEN PERRIS ATTORNEY -causes spindling.

UNITED STATES PATENT OFFICE.-

BEN' PERRIS, OF CLEVELAND, OHIO, AS SIGNOR T0 NATIONAL CARBON COMPANY, OF

CLEVELAND, OHIO, A CORPORATION OF NEW JERSEY.

METAL COATING FOR ARC-LIGHT ELECTRODES.

Specification of Letters Patent.

Patented July 27, 1915.

Application filed Octoiaer 25, 1912. Serial No. 727,742.

T 11/ M7101 ft m (1 roar-(2m:

Be it known that I, BEN Pincus, a citizen of the l nited States, and a resident of Cleveland, in the county of'Cuyahoga, in the State of ()hio, have invented new and useful ln'iprovements in Metal Coatings for ArcLight Electrodes, of which the following is a clear and, exat t description.

This invention relatesto metal coatings for a re light electrodes.

One of ihe objects is to apply the metal coating in such a manner that it will not pull away from the electrode tocause spindling when burned in the lamp.

Another object is to prevent the coating from obscuring the light by protruding above the electrode end.

()ther objectswill appear in the appended description.

in the drawings the figure shows an electrode having a coating in accordance with my invention.

Some types of electric light carbons are plated with metal, usually copper, throughout the greater part of their lengtlrto decrease the resistance, or at the holder end to A metal platecoating, such as electroplate, thin tube or other form has objectionable features when used on an. are light carbon. The plate is liable to separate. from the hot end of the electrode when burning and this Another objectionable feature is that the solid plating ofqlnetal resists the action of the arc to a greater extent than does the carbon electrode. Consequently it sometimes extends more or less above the electrode and obscures the light. This difficulty is met with, both when it is electroplated and when it is put on mechanically in the shape of a tube or other form.

I have found that if the coat is put on in the shape of a metal powder, none of the above mentioned difficulties are met with. A metal paint is first formed by mixing powdered coppe b bronze or other metals with some matrix of varnish or other sizing which sets very hard at ordinary temperatures. This paint is applied to the carbons with a fine brush or the carbons may be dipped in it and the excessallowed to drain Oil. \Vhen the paint sets it adheres very firmly and furnishes a good conductor of electricity. Since the coating' is not in the form of a continuous sheet, but exists in the form of a powder it does not pull away from the carbon nor eXtend'above the burning end of the electrode. The metal particles become sweated to the carbon at the arcing end and always remain just below the burning point.

Having described my invention what I claim is:

An arc lamp electrode having a coating of metal powder secured to it bya binder.

In testimony whereof I have hereunto signed my name in the presence of two witnesses.

BEN PERRIS. W'itnesses I. J. Amms, G. H. BROWN. 

